fix(mirror): add max auth request age configuration (#9812)

The `auth.auth_requests` table is not cleaned up so long running Zitadel
installations can contain many rows.

The mirror command can take long because a the data are first copied
into memory (or disk) on cockroach and users do not get any output from
mirror. This is unfortunate because people don't know if Zitadel got
stuck.

Enhance logging throughout the projection processes and introduce a
configuration option for the maximum age of authentication requests.

None

closes https://github.com/zitadel/zitadel/issues/9764

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

cmd/mirror/projections.go

@@ -3,6 +3,7 @@ package mirror
 import (
 	"context"
 	"database/sql"
+	"fmt"
 	"net/http"
 	"sync"
 	"time"
@@ -103,6 +104,7 @@ func projections(
 	config *ProjectionsConfig,
 	masterKey string,
 ) {
+	logging.Info("starting to fill projections")
 	start := time.Now()
 
 	client, err := database.Connect(config.Destination, false)
@@ -251,8 +253,10 @@ func projections(
 		go execProjections(ctx, instances, failedInstances, &wg)
 	}
 
-	for _, instance := range queryInstanceIDs(ctx, client) {
+	existingInstances := queryInstanceIDs(ctx, client)
+	for i, instance := range existingInstances {
 		instances <- instance
+		logging.WithFields("id", instance, "index", fmt.Sprintf("%d/%d", i, len(existingInstances))).Info("instance queued for projection")
 	}
 	close(instances)
 	wg.Wait()
@@ -264,7 +268,7 @@ func projections(
 
 func execProjections(ctx context.Context, instances <-chan string, failedInstances chan<- string, wg *sync.WaitGroup) {
 	for instance := range instances {
-		logging.WithFields("instance", instance).Info("start projections")
+		logging.WithFields("instance", instance).Info("starting projections")
 		ctx = internal_authz.WithInstanceID(ctx, instance)
 
 		err := projection.ProjectInstance(ctx)
@@ -299,7 +303,7 @@ func execProjections(ctx context.Context, instances <-chan string, failedInstanc
 	wg.Done()
 }
 
-// returns the instance configured by flag
+// queryInstanceIDs returns the instance configured by flag
 // or all instances which are not removed
 func queryInstanceIDs(ctx context.Context, source *database.DB) []string {
 	if len(instanceIDs) > 0 {